The invention relates to the area of tumor suppression. More particularly, the invention relates to tumor suppressor genes and proteins.
Mutations in tumor suppressor genes play an important role in the development of neoplasias. Manipulation of tumor suppressor gene expression can be used to prevent or treat neoplasias. Detection of mutations in tumor suppressor genes can also be used to detect neoplastic cells and genetic predispositions to neoplasias. Thus, there is a need in the art for the identification of mammalian tumor suppressor genes which can be used in methods of diagnosing, prognosing, and treating neoplastic cells in humans and other mammals.
It is an object of the invention to provide an isolated and purified human polyhomeotic 2 protein.
It is another object of the invention to provide an isolated and purified human polyhomeotic 2 polypeptide.
It is yet another object of the invention to provide an hph2 fusion protein.
It is still another object of the invention to provide a preparation of antibodies which specifically bind to a human polyhomeotic 2 protein.
It is yet another object of the invention to provide an isolated and purified subgenomic polynucleotide.
It is still another object of the invention to provide an expression construct for expressing all or a portion of a human polyhomeotic 2 protein.
It is a further object of the invention to provide a homologously recombinant cell comprising a DNA construct.
It is even another object of the invention to provide a method of identifying neoplastic tissue of a human.
It is another object of the invention to provide a method to aid in the diagnosis or prognosis of neoplasia in a human.
It is yet another object of the invention to provide a method to aid in detecting a genetic predisposition to neoplasia in a human.
It is still another object of the invention to provide a method of identifying a human chromosome 1.
It is even another object of the invention to provide a therapeutic composition for restoring a wild-type human polyhomeotic 2 function to a cell which lacks that function.
It is another object of the invention to provide a method of treating proliferative disorders.
It is still another object of the invention to provide a method of inducing a cell to differentiate.
These and other objects of the invention are provided by one or more of the embodiments described below.
One embodiment of the invention provides an isolated and purified human polyhomeotic 2 protein. The isolated and purified human pplyhomeotic 2 protein has the amino acid sequence shown in SEQ ID NO:2.
Another embodiment of the invention provides an isolated and purified human polyhomeotic 2 protein. The isolated and purified human polyhomeotic 2 protein has an amino acid sequence which is at least 85% identical to the amino acid sequence shown in SEQ ID NO:2.
Even another embodiment of the invention provides an isolated and purified human polyhomeotic 2 polypeptide. The isolated and purified human polyhomeotic 2 polypeptide consists of at least 14 contiguous amino acids selected from the amino acid sequence shown in SEQ ID NO:2.
Yet another embodiment of the invention provides a human polyhomeotic 2 fusion protein. The human polyhomeotic 2 fusion protein comprises a first protein segment and a second protein segment fused together by means of a peptide bond. The first protein segment consists of at least 14 contiguous amino acids of a human polyhomeotic 2 protein.
Still another embodiment of the invention provides a preparation of antibodies which specifically bind to a human polyhomeotic 2 protein.
Even another embodiment of the invention provides an isolated and purified subgenomic polynucleotide. The isolated and purified subgenomic polynucleotide consists of at least 11 contiguous nucleotides selected from the nucleotide sequence shown in SEQ ID NO:1.
Yet another embodiment of the invention provides an expression construct for expressing all or a portion of a human polyhomeotic 2 protein. The expression construct comprises a promoter and a polynucleotide segment. The polynucleotide segment encodes at least 14 contiguous amino acids of a human polyhomeotic 2 protein. The polynucleotide segment is located downstream from the promoter. Transcription of the polynucleotide segment initiates at the promoter.
A further embodiment of the invention provides a homologously recombinant cell. The homologously recombinant cell comprises an incorporated new transcription unit wherein the new transcription unit comprises an exogenous regulatory sequence, an exogenous exon, and a splice donor site. The transcription unit is located upstream of a coding sequence of an hph2 gene. The exogenous regulatory sequence directs transcription of the coding sequence of the hph2 gene. The new transcription unit is incorporated into the genome using segments of homologous DNA from the hph2 gene.
Still another embodiment of the invention provides a method of identifying neoplastic tissue of a human. The method comprises comparing the expression of a polyhomeotic 2 gene in a first tissue of a human suspected of being neoplastic with the expression of a polyhomeotic 2 gene in a second tissue of the human which is normal. Underexpression of the human polyhomeotic 2 gene in the first tissue identifies the first tissue as being neoplastic.
Even another embodiment of the invention provides a method to aid in the diagnosis or prognosis of neoplasia in a human. The method comprises comparing a polyhomeotic 2 gene, mRNA, or protein in a first tissue of a human suspected of being neoplastic with a polyhomeotic 2 gene, mRNA, or protein in a second tissue of a human which is normal. A difference between the polyhomeotic 2 genes, mRNAs, or proteins in the first and second tissues indicates neoplasia in the first tissue.
Another embodiment of the invention provides a method to aid in detecting a genetic predisposition to neoplasia in a human. The method comprises comparing a polyhomeotic 2 gene, mRNA, or protein in a fetal tissue of a human with a wild-type human polyhomeotic 2 gene, mRNA, or protein. A difference between the polyhomeotic 2 gene, mRNA, or protein in the fetal tissue of the human and the wild-type human polyhomeotic 2 gene, mRNA, or protein indicates a genetic predisposition to neoplasia in the human.
Yet another embodiment of the invention provides method of identifying a human chromosome 1. The method comprises the steps of contacting a preparation of metaphase human chromosomes with a nucleotide probe comprising at least 12 contiguous nucleotides selected from the nucleotide sequence shown in SEQ ID NO:1 and detecting a region of a chromosome which specifically hybridizes to the nucleotide probe. A region of a chromosome which specifically hybridizes to the nucleotide probe is identified as a region of human chromosome 1.
Even another embodiment of the invention provides a therapeutic composition for restoring a wild-type human polyhomeotic 2 function to a cell which lacks that function. The therapeutic composition comprises all or a portion of a wild-type human polyhomeotic 2 gene or expression product and a pharmaceutically acceptable carrier. Said all or a portion of the wild-type human polyhomeotic 2 gene or expression product is capable of restoring a wild-type polyhomeotic 2 function to a cell.
Still another embodiment of the invention provides a method of treating proliferative disorders. The method comprises the step of administering to a human a composition comprising all or a portion of a wild-type human polyhomeotic 2 gene or expression product. Said all or a portion of the wild-type human polyhomeotic 2 gene or expression product is capable of restoring or enhancing a wild-type polyhomeotic 2 function to a cell.
A further embodiment of the invention provides a method of inducing a cell to change its pattern of differentiation. The method comprises the step of contacting a cell with an effective amount of a composition comprising all or a portion of a human polyhomeotic 2 gene or expression product. Said all or a portion of the human polyhomeotic 2 gene or expression product is capable of inducing the cell to change its pattern of differentiation.
The present invention thus provides the art with a novel human tumor suppressor gene called polyhomeotic 2 (hph2). The hph2 gene and protein can be used, inter alia, as therapeutic, prognostic, and diagnostic tools for proliferative and developmental disorders and to identify a p34.3 region of a human chromosome 1.